Electrotherapeutic apparatus



Jan. 25, 1938.

J. HOFMAN N ELECTROTHERAPEUIIC APPARATUS Filed Dec; 21, 19.53

Patented Jan. 25, 1938 UNITED STATES PATENT OFFICE many,

assignor to Elektricitiitsgesellschaft "Sanititf G. m. b. IL, Berlin, Germany, a corporation of Germany Application December '21, 1933, Serial No. 703,383 In Germany December 23, 1932 4 Claims.

This invention relates to electro-therapeutic apparatus, and more particularly to short and/or ultra short wave diathermic apparatus wherein the high frequency oscillations are produced by a 5 series spark gap. 7

One of the objects of the invention is to provide diathermy apparatus which may be used for long wave as well as short wave diathermy.

Another object ofthe invention is to providediathermy apparatus having a short wave oscillatorycircuit and along wave oscillatory circuit and means whereby either of said circuits may be supplied with oscillatory energy.

A further object of the invention is to provide a short or ultra short wave diathermy apparatus with a long wave attachment to enable said apparatus to be used alternatively for either short or long wave treatment- These and such other objects and aims of the invention as may hereinafter appear, as well as the invention itself, will be clearly understood from the following description, taken in connection with the. accompanying drawing, of illustrative apparatus embodying the features of 25 the invention, the true scope of the invention being more particularly pointed out in the appended claims. 1

In the drawing:

Fig. 1 is a diagrammatic illustration of one illustrative embodiment of the invention:

Fig. 2 shows a cabinet containing a short wave diathermy apparatus, a long wave apparatus being separately afiixed externally thereto..

As explained the invention contemplates the provision of means whereby said diathermy apparatus ma; be used for long wave as well as short wave diathermy.

Referring to Fig. 1, the adaptation to long wave diathermy is conveniently obtained by the use of an auxiliary device. Said device may be connected electrically to the connecting bushings of the electrodes of the short wave generator. Where a capacity or inductive coupling is used between the oscillatory circuit and the short wave treating circuit, thus necessitating the provision of protective condensers in the-treating circuit to protect the patient against low frequency alternations, said auxiliary device "or attachment may consist of a self-inductance coil of suitable dimensions and connecting the connecting terminal sleeves of the apparatus together. Suitable means may be provided for a fine adjustment of the long wave energy. Within the scope of the invention any suitable .regulating means may be provided for this P pose, such for example as a potentiometer providedparallel tov said auxiliary spark gap 36 which connects the terminals of said condenser directly one to the other. Said .spark-gap may be of any suitable shape but herein is shown as a substantially circular memher. An auxiliary circuit ,comprising a capacity 38 and self-inductance 40 is provided parallel to said spark gap, said self-inductance 46] being as large as possible while stillpermitting said capacity 38 to exert an adequate quenching action upon the said spark gap. Said impulse circuit comprising said condenser 34 and-series spark gap 35 may be coupled in any suitable manner (by an inductive, or capacity coupling or directly by conductors) to the treating circuit. Herein said capacity or condenser 34 is used for this purpose, condensers 42, 42 being provided to protect the patient from low.frequency alternations, in the-conductors leading to the connecting bushings .44 of the short wave condenser electrodes.

In the illustrative embodiment of the invention said auxiliary device or attachmentfor the gen-' eration of long waves comprises a self inductance coil 46 which is electrically; connected to the terminal bushings for connecting with the electrodes, said coil 46 being of such dimensions that it forms a long wave oscillatory circuit in conjunction with said condensers 42, 42. A potentiometer 48 of any suitable conventional construction may be provided parallel to said coil 45 for effecting a fine regulation or adjustment in .order that the long wave energy may be conveyed with the desired strength to the;connecting terminals 50 of the diathermy and surgical electrodes. g

In Fig. 2 there is shown a cabinet containing the 'short wave generator, a switch 52 being provided for connecting the apparatus to and disconnecting it from the main supply of electrical energy. Regulation of the impulse circuit relative to the treating circuit is eifected by the rotary."

handle 54. Herein the long wave generating device is shown as a separate attachment herein contained in a removable casing or container 56, provided with the connecting contact pins to be inserted in suitable sockets in the'frontwall of said cabinet when the apparatusis to be used for long wave treatment. When it is to be used for shortwave treatment the said connecting contact pins are withdrawn from said sockets forming the terminals of the short wave circuit, and the whole container 56 is removed, and a set of treating electrodes are connected up to the said sockets for the short wave treatment. The long wave energy is regulated by the rotary handle 58.

It .will be apparent to those skilled in the art that said auxiliary device for generating long wave oscillations could be built in to the short wave apparatus parallel to the connecting contact bushings 46. tional means would have to be provided for cutting out the coil 46 when it is desired to make short wave treatments. r

I am aware that the invention may be embodied in other specific forms without departing from thespirit or essential attributes thereof, and I therefore desire the present embodiments to be considered in all respects as illustrative and not restrictive reference being had to the appended claims rather than to the foregoing description to indicate the true scope of the invention.

I claim:

1. Electro-therapeutic apparatus for generating short or ultra short waves, comprising, in combination, means to generate short waves including an impulse circuit; containing a condenser; a series spark-gap having its two ends connected to the two terminals, respectively, of said condenser; an auxiliary circuit parallel to said spark gap; a self-inductance and a capacity in said auxiliary circuit, said self-inductance being as large as feasible without danger of arcing at said spark-gap terminals serving to connect said short wave generator with the electrodes for short wave treatment; a long wave generating circuit corn-' prising said spark gap and condenser means and means to connect said long wave generating circult to said terminals.

2. Electra-therapeutic apparatus for generating In such case any suitable conven short or ultra short waves, comprising, in combination, an impulse circuit; a condenser in said circuit; a series spark-gap having its two ends connected to the two terminals, respectively, of said condenser; an auxiliary circuit parallel to said spark-gap; a self-inductance and a capacity in said auxiliary circuit, said self-inductance being as large as feasible without danger of arcing at said spark-gap; a short wave treating circuit; a capacity coupling between said short wave treating circuit and,,said impulse circuit; condensers in said short wave treating circuit; terminals for connecting electrodes with said short wave treatingrcircuit; an attachment forconnection to said terminals and comprising a self-inductance coil connecting said terminals, said coil cooperating with said condensers in said treating circuit to generate long wave oscillations for. passing heat through the tissues ofthe body and for high frequency surgical operations.

3. Electro-therapeutic apparatus for generating short or ultra short waves according to claim 2 comprising a potentiometer provided parallel to said self-inductance coil of said attachment for fine regulation or adjustment of the long wave energy.

4. Apparatus of the class described comprising, in combination, a source of oscillations; at short .wave oscillating circuit supplied by said source of oscillations; a treating circuit'coupled to said source of oscillations and provided with terminals for connection with electrodes to deliver short wave oscillations; a self-inductance coil; and means to connect said coil to said terminals, said coil thus forming with said treating circuit a long wave oscillating circuit supplied by said source of oscillations to deliver long wave oscillations.

JOSEF HOFMANN. 

